Enhanced Potentiometric Detection of Hydrogen Peroxide Using a Platinum Electrode Coated with Nafion

详细信息    查看全文

• 作者：Marc Parrilla ; Rocí ; o Cá ; novas and Francisco J. Andrade
• 刊名：Electroanalysis
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：29
• 期：1
• 页码：223-230
• 全文大小：1198K
• ISSN：1521-4109

文摘

The potentiometric response to hydrogen peroxide of a platinum electrode coated with a layer of Nafion is presented. The results show that the Nafion membrane acts as an effective permselective barrier, thus significantly reducing the response to some redox active species, such as ascorbate. Even more interesting, these coated electrodes show a significantly enhanced sensitivity to hydrogen peroxide (H₂O₂) when the measurements are performed in solutions of high ionic strength. The influence of pH, ionic strength and supporting electrolyte on this enhancement are presented. Under optimized conditions these coated electrodes show a linear dependence with the logarithm of the concentration of H₂O₂, with sensitivities of −125.1±5.9 mV decade⁻¹ (several times higher than the bare electrodes) and a linear range that spans from 10⁻⁵ M to 10⁻³ M of H₂O₂. Preliminary studies suggest that the coupling between the redox potential on the Pt electrode and the Donnan potential of the membrane plays a role on this enhancement. Considering this improved sensitivity, selectivity, stability and linear ranges, this system shows promise as a future platform to build enzyme-based potentiometric biosensors.